Two-level Continuous Topology Optimization in Structural Mechanics

In the current industry, the development of optimized mechanical components able to satisfy the customer requirements evolves quickly. Therefore, companies are asked for efficient solutions to improve their products in terms of stiffness and strength. In this sense, Topology Optimization has been extensively used to determine the best topology of structural components from the mechanical point of view. Its main objective is to distribute a given amount of material into a predefined domain to reach the maximum overall stiffness of the component. Besides, high-resolution solutions are essential to define the final distribution of material. Standard Topological Optimization tools are able to propose an optimal topology for the whole component, but when small topological details are required (i.e. trabecular-type structures) the computational cost is prohibitive. In order to mitigate this issue, the present work proposes a two-level topology optimization method to solve high-resolution problems by using density-based methods. The proposed methodology includes three steps: The first one subdivides the whole component in cells and generates a coarse optimized low-definition material distribution assigning one different density to each cell. The second one uses an equilibrating technique that provides tractions continuity between adjacent cells, thus ensuring the material inter-cell continuity after the cells optimization process. Finally, each cell is optimized at fine scale taking as input data the densities and the equilibrated tractions obtained from the macro problem. The main goal of this work is to efficiently solve high-resolution topology optimization problems using density-based methods, which would be unaffordable with standard computing facilities and the current methodologies.Comment: 23 page

Effects of kangaroo mother care in the NICU on the physiological stress parameters of premature infants: A meta-analysis of RCTs

Objective: The aim of this study was to analyze the randomised controlled trials that explored the effect of kangaroo mother care on physiological stress parameters of premature infants. Methods: Two independent researchers performed a systematic review of indexed studies in PubMed, Embase, CINAHL, Cochrane and Scopus. We included data from randomized controlled trials measuring the effects of kangaroo care compared to standard incubator care on physiological stress outcomes, defined as oxygen saturation, body temperature, heart rate and respiratory rate. The PRISMA model was used to conduct data extraction. We performed a narrative synthesis of all studies and a meta-analysis when data were available from multiple studies that compared the same physiological parameters with the kangaroo method as an intervention and controls and used the same outcome measures. Results: Twelve studies were eligible for inclusion in this meta-analysis. According to statistical analysis, the mean respiratory rate of preterm infants receiving KMC was lower than that of infants receiving standard incubator care (MD, −3.50; 95% CI, −5.17 to −1.83; p < 0.00001). Infants who received kangaroo mother care had a higher mean heart rate, oxygen saturation and temperature, although these results were not statistically significant. Conclusions: Current evidence suggests that kangaroo care in the neonatal intensive care unit setting is a safe method that may have a significant effect on some of the physiological parameters of stress in preterm infants. However, due to clinical heterogeneity, further studies are needed to assess the effects of physiological stress in the neonatal intensive care unit on the development of preterm infants

Mapping the Field in Stress, Anxiety, and Postpartum Depression in Mothers of Preterm Infants in Neonatal Intensive Care

Objective: The main aim of this study was to describe and conduct a bibliometric analysis of the state of research on stress, anxiety, and postpartum depression in mothers of preterm infants in the Neonatal Intensive Care Unit. Background: Women affected by premature births are particularly exposed to mental health difficulties in the postpartum period. The desire to comprehend and the growing interest in research on stress, anxiety, and postpartum depression in mothers of preterm infants in neonatal intensive care have led to a substantial rise in the number of documents in this field over the last years. Thus, it makes it vital to regularly review the state of knowledge on this phenomenon in order to identify progress and constraints, to stimulate reflection, and to encourage progress in future research. Method: This study examined 366 articles published in the Scopus database (1976–2020). Keyword analysis was also used to identify hot research trends to be developed in future studies. This study complies with the PRISMA-Scr guidelines for quality improvement research in the EQUATOR network. Results: Our results reveal that research in this field is in a period of high production and allows this flourishing body of work to be organized into different periods, highlighting the most important themes. In such a way, our research enriches the lively field by presenting a comprehensive understanding of the field. Discussion: The key contribution of this study is the development of a conceptual map of research on stress, anxiety, and postpartum depression in mothers of preterm infants in neonatal intensive care units

Effects of infant feeding with goat milk formula or cow milk formula on atopic dermatitis: protocol of the randomised controlled Goat Infant Formula Feeding and Eczema (GIraFFE) trial

Atopic dermatitis (AD) is a chronic, inflammatory skin condition significantly affecting quality of life. A small randomised trial showed an approximately one-third lower incidence of AD in goat milk formula-fed compared with cow milk formula-fed infants. However, due to limited statistical power, AD incidence difference was not found to be significant. This study aims to explore a potential risk reduction of AD by feeding a formula based on whole goat milk (as a source of protein and fat) compared with a formula based on cow milk proteins and vegetable oils. Methods and analysis: This two-arm (1:1 allocation), parallel, randomised, double-blind, controlled nutritional trial shall enrol up to 2296 healthy term-born infants until 3 months of age, if parents choose to start formula feeding. Ten study centres in Spain and Poland are participating. Randomised infants receive investigational infant and follow-on formulas either based on whole goat milk or on cow milk until the age of 12 months. The goat milk formula has a whey:casein ratio of 20:80 and about 50% of the lipids are milk fat from whole goat milk, whereas the cow milk formula, used as control, has a whey:casein ratio of 60:40 and 100% of the lipids are from vegetable oils. The energy and nutrient levels in both goat and cow milk formulas are the same. The primary endpoint is the cumulative incidence of AD until the age of 12 months diagnosed by study personnel based on the UK Working Party Diagnostic Criteria. The secondary endpoints include reported AD diagnosis, measures of AD, blood and stool markers, child growth, sleep, nutrition and quality of life. Participating children are followed until the age of 5 years

Guía de práctica clínica SENPE/SEGHNP/SEFH sobre nutrición parenteral pediátrica

Introduction: Parenteral nutrition (PN) in childhood is a treatment whose characteristics are highly variable depending on the age and pathology of the patient. Material and methods: The Standardization and Protocols Group of the Spanish Society for Parenteral and Enteral Nutrition (SENPE) is an interdisciplinary group formed by members of the SENPE, the Spanish Society of Gastroenterology, Hepatology and Pediatric Nutrition (SEGHNP) and the Spanish Society of Hospital Pharmacy (SEFH) that intends to update this issue. For this, a detailed review of the literature has been carried out, looking for the evidences that allow us to elaborate a Clinical Practice Guide following the criteria of the Oxford Center for Evidence-Based Medicine. Results: This manuscript summarizes the recommendations regarding indications, access routes, requirements, modifications in special situations, components of the mixtures, prescription and standardization, preparation, administration, monitoring, complications and home NP. The complete document is published as a monographic number. Conclusions: This guide is intended to support the prescription of pediatric PN. It provides the basis for rational decisions in the context of the existing evidence. No guidelines can take into account all of the often compelling individual clinical circumstances.Introducción: la nutrición parenteral (NP) en la infancia es un tratamiento cuyas características son muy variables en función de la edad y la patología que presente el paciente. Material y métodos: el grupo de Estandarización y Protocolos de la Sociedad Española de Nutrición Parenteral y Enteral (SENPE) es un grupo interdisciplinar formado por miembros de la SENPE, Sociedad Española de Gastroenterología, Hepatología y Nutrición Pediátrica (SEGHNP) y Sociedad Española de Farmacia Hospitalaria (SEFH) que pretende poner al día este tema. Para ello, se ha realizado una revisión pormenorizada de la literatura buscando las evidencias que nos permiten elaborar una Guía de Práctica Clínica siguiendo los criterios del Oxford Centre for Evidence-Based Medicine. Resultados: este manuscrito expone de forma resumida las recomendaciones en cuanto a indicaciones, vías de acceso, requerimientos, modificaciones en situaciones especiales, componentes de las mezclas, prescripción y estandarización, preparación, administración, monitorización, complicaciones y NP domiciliaria. El documento completo se publica como número monográfico. Conclusiones: esta guía pretende servir de apoyo para la prescripción de la NP pediátrica. Constituye la base para tomar decisiones en el contexto de la evidencia existente. Ninguna guía puede tener en cuenta todas las circunstancias clínicas individuale

Predictors of Response to Exclusive Enteral Nutrition in Newly Diagnosed Crohn´s Disease in Children: PRESENCE Study from SEGHNP

Exclusive enteral nutrition (EEN) has been shown to be more effective than corticosteroids in achieving mucosal healing in children with Crohn´s disease (CD) without the adverse effects of these drugs. The aims of this study were to determine the efficacy of EEN in terms of inducing clinical remission in children newly diagnosed with CD, to describe the predictive factors of response to EEN and the need for treatment with biological agents during the first 12 months of the disease. We conducted an observational retrospective multicentre study that included paediatric patients newly diagnosed with CD between 2014–2016 who underwent EEN. Two hundred and twenty-two patients (140 males) from 35 paediatric centres were included, with a mean age at diagnosis of 11.6 ± 2.5 years. The median EEN duration was 8 weeks (IQR 6.6–8.5), and 184 of the patients (83%) achieved clinical remission (weighted paediatric Crohn’s Disease activity index [wPCDAI] 15 mg/L and ileal involvement tended to respond better to EEN. EEN administered for 6–8 weeks is effective for inducing clinical remission. Due to the high response rate in our series, EEN should be used as the first-line therapy in luminal paediatric Crohn’s disease regardless of the location of disease and disease activityS

The Beaker phenomenon and the genomic transformation of northwest Europe

From around 2750 to 2500 bc, Bell Beaker pottery became widespread across western and central Europe, before it disappeared between 2200 and 1800 bc. The forces that propelled its expansion are a matter of long-standing debate, and there is support for both cultural diffusion and migration having a role in this process. Here we present genome-wide data from 400 Neolithic, Copper Age and Bronze Age Europeans, including 226 individuals associated with Beaker-complex artefacts. We detected limited genetic affinity between Beaker-complex-associated individuals from Iberia and central Europe, and thus exclude migration as an important mechanism of spread between these two regions. However, migration had a key role in the further dissemination of the Beaker complex. We document this phenomenon most clearly in Britain, where the spread of the Beaker complex introduced high levels of steppe-related ancestry and was associated with the replacement of approximately 90% of Britain’s gene pool within a few hundred years, continuing the east-to-west expansion that had brought steppe-related ancestry into central and northern Europe over the previous centuries

Spatiotemporal Characteristics of the Largest HIV-1 CRF02_AG Outbreak in Spain: Evidence for Onward Transmissions

Background and Aim: The circulating recombinant form 02_AG (CRF02_AG) is the predominant clade among the human immunodeficiency virus type-1 (HIV-1) non-Bs with a prevalence of 5.97% (95% Confidence Interval-CI: 5.41–6.57%) across Spain. Our aim was to estimate the levels of regional clustering for CRF02_AG and the spatiotemporal characteristics of the largest CRF02_AG subepidemic in Spain.Methods: We studied 396 CRF02_AG sequences obtained from HIV-1 diagnosed patients during 2000–2014 from 10 autonomous communities of Spain. Phylogenetic analysis was performed on the 391 CRF02_AG sequences along with all globally sampled CRF02_AG sequences (N = 3,302) as references. Phylodynamic and phylogeographic analysis was performed to the largest CRF02_AG monophyletic cluster by a Bayesian method in BEAST v1.8.0 and by reconstructing ancestral states using the criterion of parsimony in Mesquite v3.4, respectively.Results: The HIV-1 CRF02_AG prevalence differed across Spanish autonomous communities we sampled from (p &lt; 0.001). Phylogenetic analysis revealed that 52.7% of the CRF02_AG sequences formed 56 monophyletic clusters, with a range of 2–79 sequences. The CRF02_AG regional dispersal differed across Spain (p = 0.003), as suggested by monophyletic clustering. For the largest monophyletic cluster (subepidemic) (N = 79), 49.4% of the clustered sequences originated from Madrid, while most sequences (51.9%) had been obtained from men having sex with men (MSM). Molecular clock analysis suggested that the origin (tMRCA) of the CRF02_AG subepidemic was in 2002 (median estimate; 95% Highest Posterior Density-HPD interval: 1999–2004). Additionally, we found significant clustering within the CRF02_AG subepidemic according to the ethnic origin.Conclusion: CRF02_AG has been introduced as a result of multiple introductions in Spain, following regional dispersal in several cases. We showed that CRF02_AG transmissions were mostly due to regional dispersal in Spain. The hot-spot for the largest CRF02_AG regional subepidemic in Spain was in Madrid associated with MSM transmission risk group. The existence of subepidemics suggest that several spillovers occurred from Madrid to other areas. CRF02_AG sequences from Hispanics were clustered in a separate subclade suggesting no linkage between the local and Hispanic subepidemics

Prevalencia de obesidad, resistencia insulínica y síndrome metabólico en adolescentes: factores asociados

Tesis Univ. Granada. Departamento de Pediatrí